Mechanical parking systems are well known in which cars are loaded by suitable crane mechanisms into stalls arranged in multiple tiers. One type of such prior art parking systems utilizes a craneway running between two, multiple story, parking structures, the parking structures have a row of stalls on each story to receive the cars from the elevators. Such a system is described, for example, in U.S. Pat. No. 2,714,456, which issued in the name of the present inventor.
In the system described in the patent, a series of structural units extend transversely across a parking lot, and the units are spaced from one another by the craneways. Each structural unit described in the patent comprises a ground story and multiple tiers above the ground story. The units are of substantially rectangular shape as seen in plan view, and they include a longitudinal row of transversely disposed stalls on each story. Elevator mechanisms adapted to move both vertically and horizontally in the craneways to service the various stalls.
U.S. Pat. No. 2,840,248 which issued June 24, 1958, describes a self-propelled traverse dolly, one of which may be carried on each elevator platform in the above described system for moving the cars onto and off the elevator mechanisms, both at ground level and at the selected stalls on the selected stories of each parking unit.
In the operation of the prior art parking system described above, a car is parked by its owner in a loading area on the ground level adjacent to one of the craneways of the system. The operator of the parking facility then controls one of the elevator mechanisms to bring the elevator platform to its ground level loading position in alignment with the car. The self-propelled traverse dolly is then operated to move it off the elevator platform, and under the car, and then to move it and the car onto the elevator platform. The elevator platform is then elevated, and the elevator mechanism is then moved horizontally to a position in alignment with a selected stall of the system. The dolly is again operated to move it and the car from the elevator platform into the selected stall. The dolly is then returned to the elevator platform. The operation of the system is reversed when the car is to be redelivered to its owner.
In the system of the present invention, a cleat lift platform is provided in each of a variety of locations on the ground floor of the car parking system in positions for permitting cars to be loaded onto, or unloaded from, the elevator platforms in the elevator mechanisms in the various craneways by the traverse dollies. Each cleat lift platform is controlled to raise a supported car up a predetermined distance on traverse cleats, so as to permit the corresponding dolly to move under the car, extend its transverse supporting forks between the cleats, raise the car on its forks up from the cleats, and load the car onto the elevator platform; and to repeat the process on the return of the car.